The ethtool is a utility for displaying and configuring Ethernet card driver and hardware settings. Changes made using ethtool are runtime changes and not persistence changes. Whether or not it is installed by default will depend on the distribution in use. The ethtool utility has a great many options for gathering information.
Syntax
The syntax of the ethtool command is:
# ethtool [options] {device name}
ethtool Command Options
The following table describes some common ethtool command options.
| Option | Used To |
|---|---|
| -S {interface} | Show statistics for a NIC. |
| -i {interface} | Show driver information for a NIC. |
| -t {interface} | Execute a self-test on the NIC. |
| -s {interface} {setting} {value} | Change some of a NIC’s settings, such as its speed and duplex mode. |
| -f {interface} {image} | Write (“flash”) a firmware image to the NIC. |
ethtool Command Examples
1. Display the current settings for an interface:
# ethtool eth0
2. Display the driver information for an interface:
# ethtool --driver eth0
3. Display all supported features for an interface:
# ethtool --show-features eth0
4. Display the network usage statistics for an interface:
# ethtool --statistics eth0
5. Blink one or more LEDs on an interface for 10 seconds:
# ethtool --identify eth0 10
6. Set the link speed, duplex mode, and parameter auto-negotiation for a given interface:
# ethtool -s eth0 speed 10|100|1000 duplex half|full autoneg on|off
7. Display the Ethernet interface driver settings using ethtool command as shown here:
# ethtool -i enp0s3
8. Modifying the Ethernet interface settings using ethtool command as shown:
# ethtool --change enp0s3 speed 10 duplex half autoneg off